UL94 Flame Rating

Integra polycarbonate enclosures carry the 5VA rating, the highest classification in the UL94 Standard.

UL94 is a standard for the Safety of Flammability of Plastic Materials for Parts in Devices and Appliances, a classification for how plastics react to heat or flame. The thermoplastic used by Integra Enclosures for its NEMA enclosures carries a 5VA rating, meaning it performs exceptionally well in flame-susceptible environments.

UL94 Flame Rating Explained

This test, which is conducted on a thin sample measuring 5” long by ½” wide, gives engineers a consistent standard for measuring how flammable a plastic is. Integra’s polycarbonate rates at 5VA, which is the best possible rating (i.e. least flammable). As a self-extinguishing material, polycarbonate requires no protective coating. The 5VA rating means that burning stops within 60 seconds on vertical bar and plaque specimens, without a hole (on the plaque specimen) or any drips.

Enclosures made from fiberglass commonly rate at HB – the lowest UL94 rating. The 5VA rating is significantly more stringent; for example, the flame ignition source is five times hotter than in the less stringent classifications. In a demanding enclosure application, this could spell the difference between consistent quality and a product failure.

If high temperatures and fire are at all a factor in your application, polycarbonate should be at the top of your list for enclosure materials. Fortunately, the most fire-retardant enclosures also feature excellent impact strength, UV resistance and easy modification – all at a reasonable price and high recyclability.

If you’re still not sure whether polycarbonate enclosures will stand up to your technical needs, browse our technical resources or contact us. We can help you find the perfect enclosure for your space, equipment and application.

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